Technical Field
The present invention relates to a technology of display devices, and in particular, to an in-cell touch display device and operating methods thereof.
Related Art
There are two major technical development trends of touch display devices at present: an out-cell technology and an in-cell technology. In the out-cell technology, a display panel having no touch function is overlaid with a touch panel, while in the in-cell technology, a touch sensor is directly placed inside a pixel structure of a display panel. Compared with a touch display device using the out-cell technology, a touch display device using the in-cell technology has an advantage of thinner thickness.
In an in-cell touch display device, at least one touch sensing period is inserted in each frame period, and during each touch sensing period, while the gate driving operation is suspended, a gate potential level of a driving transistor in a shift register needs to be maintained for a preset period of time after the current touch sensing period, so that the shift register can generate a corresponding gate pulse according to the gate potential level of the driving transistor after the current touch sensing period ends. However, leakage exists along the plurality of transistors in the shift register; as a result, the gate potential and the gate pulse generated by the shift register is lower than a preset level, which causes a striped pattern problem on a frame.